The present invention is directed to anisotropic heat-curable monomers.
Multi-functional heat-curable monomers are known which can be employed in the production of thermosetting composites such as, for example, epoxy-based compositions. However, one disadvantage with such known thermosetting compositions is that they tend to shrink to an undesirable degree subsequent to the cross-linking reaction.
U.S. Pat. No. 4,283,551 (issued to Chow et al) discloses acetylene-terminated polyesters which are prepared by reacting a hydroxyphenylacetylene with a diacid chloride of an aromatic dibasic acid such as 4,4'-benzophenone dicarboxylic acid dichloride. However, the polyesters disclosed therein are stated to have curing temperatures which are disadvantageously high (i.e., on the order of 250.degree. to 400.degree. C.).
It is therefore desirable to provide heat-curable monomers which can be employed in the production of thermosetting resins and which exhibit a reduced tendency to shrink upon curing.
It is also desirable to provide heat-curable monomers which exhibit self-reinforcing characteristics as a result of molecular orientation in the cross-linked resin.
It is also desirable to provide a heat-curable monomer which can be cured at desirably low temperatures.